MCQ
If the external force acting on a system have zero resultant, the centre of mass:
- AMust not move.
- BMust not accelerate.
- CMay move.
- DMay accelerate.
✓
Answer
- Must not accelerate.
- May move.
Explanation:
If the external force acting on a system has zero resultant,
then, acceleration of centre of mass $=\frac{\overrightarrow{\text{F}}_{\text{net}}}{\text{M}}=0.$
However, it may move uniformly with constant velocity.
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